I don't want to throw completely baseless statistics, but I would guess over 95% of the world either a) does not have access to that kind of thing, or b) has other priorities, financially, or c) does not care about this because they are either not informed or they know this exists but is not important enough for them to actually do it.
And if you are from US remember, western countries where these things are easily available and people can generally afford it are only small percentage of the world's population.
And if people are not doing it enough in western nations where we do have access, then my posting this serves to increase awareness in this small hn community.